name: Optimize images

# **What it does**: Optimize images.

# **Why we have it**: Reduce bandwidth needs.

# **Who does it impact**: Docs engineering.

on:

workflow_dispatch:

pull_request:

paths:

- '**/*.png'

permissions:

contents: write

pull-requests: write

jobs:

optimize-images-on-pr:

# We can't make commits on forks

if: github.repository == 'github/docs-internal'

runs-on: ubuntu-latest

steps:

- name: Check out repo on head ref

uses: actions/checkout@93ea575cb5d8a053eaa0ac8fa3b40d7e05a33cc8

with:

ref: ${{ github.head_ref }}

# Need to specify a PAT here because otherwise GITHUB_TOKEN is used

# by default. Workflows won't trigger in that case because actions

# performed with GITHUB_TOKEN don't trigger other workflows.

token: ${{ secrets.DOCS_BOT_PAT_READPUBLICKEY }}

- name: Check out base ref

run: git fetch --no-tags --depth=1 origin $GITHUB_BASE_REF

- name: Install the Optipng package

run: sudo apt-get update && sudo apt-get -y install optipng

- name: Run optipng on new or changed images

run: |

set -e # exit when any command fails

echo "Ensure we can view $GITHUB_BASE_REF"

git checkout $GITHUB_BASE_REF

echo "Ensure we can view $GITHUB_HEAD_REF"

git checkout $GITHUB_HEAD_REF

echo "List the files that changed"

git diff --name-only --diff-filter=d $GITHUB_BASE_REF $GITHUB_HEAD_REF

echo "Run optipng on pngs in from the diff"

git diff --name-only -z --diff-filter=d $GITHUB_BASE_REF $GITHUB_HEAD_REF -- '*.png' | xargs -0 optipng -nx

- name: Make a commit and a push

run: |

echo "If there's no changes, exit"

if [[ ! `git status --porcelain` ]]

then

echo "No changes found"

exit 0

fi

echo "Make a commit"

git config user.name github-actions

git config user.email github-actions@github.com

git add "*.png"

git commit --message="Optimize images"

echo "Push up changes"

git push

env:

GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}